[patch] Create a preference for address duplicate detection to include buildings and POIs, not just plain address nodes

[zyphlar]

Currently, if a building area or business node is tagged with an address but a new address POI is created nearby, JOSM and MapWithAI don't detect it as a duplicate. This is a sane and liberal default for most people who don't want excessive warnings, however it isn't strictly accurate: "123 Main Street, Unit B" probably shouldn't exist in two places at once.

The main exception to this of course is if there are two un-mergeable businesses or POIs at the same location that do have the same address.

This patch allows the user to select if they want more extensive duplicate address detection, which scans all objects in an area (including buildings, businesses, POIs, etc) not just abstract floating address nodes. It includes all such object in the detection routine, and downgrades the alert from WARNING to OTHER for objects with identical addresses but differing "name" tags.